Update dependency Polyfill to 9.0.0-beta.18 (#1926)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

Directory.Packages.props

@@ -27,7 +27,7 @@
         <PackageVersion Include="JetBrains.dotCover.CommandLineTools" Version="2024.3.8" />
 
         <PackageVersion Include="JetBrains.ReSharper.GlobalTools" Version="2024.3.8" />
-        <PackageVersion Include="Polyfill" Version="9.0.0-beta.17" />
+        <PackageVersion Include="Polyfill" Version="9.0.0-beta.18" />
         <PackageVersion Include="Serilog.Sinks.Spectre" Version="0.5.0" />
         <PackageVersion Include="TUnit" Version="0.58.3" />
         <PackageVersion Include="TUnit.Core" Version="0.58.3" />